‘Detour’ Audio Tours Reveal Cities’ Fascinating BackstoriesA new app offers a dose of augmented reality in the form of a kicked up audio guide. As you walk around a city, the app geolocates you and, in time with your walking pace, offers historical tidbits about the world around you that you otherwise might’ve walked past without really seeing. The only obvious downside is that it’s not available in a ton of cities yet.—Julia Sklar

The Forgotten Father of EnvironmentalismMy German grandfather was fascinated by Humboldt, who turns out to have been “this first scientist to talk about harmful human-onduced climate change.” —Linda Lowenthal, copy chief

The Year in Fungi A roundup of newly found eukaryotes. —J. Juniper Friedman, associate Web producer